automatic transmission DATSUN PICK-UP 1977 User Guide

OPERATI
NG

PRESSURE
OF

BOOST
CONTROLLED

DECELERATION

DEVICE
B
C
D
D

ADJUSTMENT

CHECKING
a
C
D
D
CIRCUIT

WITH
FUNCTION
TEST

CONNECTOR

Manual
transmission
models

I

Check
for

continuity
between

@

and@
at
a

speed
of
zero
km
Refer

to

Figure
ET
30

B
C
D

D
circuit
is

functioning

properly
if

continuity
exists
and
volt

meter

reading
is
0
volt
d
c
in

step
2

below

If

continuity
does
not
exist
check

for
disconnected
connector
and
or

faulty

amplifier
speed
detecting

switch
or
B
C

D
D
solenoid
valve

2
Check
for

presence
of

voltage

across

@
and

@
at
a

speed
of
more

than
16
km
h

10
MPH
Refer
to

Figure
ET
31

Conduct

this
test

by
one
of

the

following
two

methods

i
Raising

up
rear
axle

housing
with

stand

2
Chassis

dynamometer
test

If
voltmeter

reading
is

0
volt
at

a

speed
of

more
than
16

km
h
10

MPH
circuit
is

functioning
prop

erly

If
voltmeter

reading
is

not
0
volt

check
for
disconnected
connector

burned
fuse

faulty

amplifier

B
C
D
D

solenoid
valve
or

speed

detecting
switch

3

If

by
above
checks

faulty
part
or

unit
is
located
it

should
be
removed

and
tested

again
If

necessary
replace

Automatic
transmission

models

I

With
inhibitor

switch
ON
UN

or
P

position
check
for

presence
of

voltage
across

@
and

@
Refer
to

Figure
ET
30

If

voltmeter

reading
is

12
volts

d
c

B
C
D
D

circuit
is

func

tioning
properly
Engine
Tune

up

If
voltmeter

reading
is

zero
check

for
disconnected

connector

faulty

solenoid
valve
or
inhibitor
switch
erly

If
ohmmeter

reading
is

32
ohms
or

above
check
for

poor
connection

of

connector

faulty
B

C
D
D

sole

noid
valve

or
inhibitor

relay

3

If

by
above
checks

faulty
part
or

unit
is

located
it
should
be
removed

and
tested

again
If

necessary
replace
2

With
inhibitor

switch
OFF

41
2
D
or
R

position

check
for
resistance

between

@
and

@
Refer

to

Figure
ET
31

If

ohmmeter

reading
is
25
ohms
or

below
circuit
is

functioning
prop

l

E
r
1

Ignition

key

2

Fuse

3

Amplifier

4

Speed
detecting
switch

Above
10

mph
OFF

Below

10

mph
ON

5

Function
test
connector

6
B
C
D
D

solenoid
valve

EF711

Fig
ET

30
B
C
D
D
circuit
with

function
tedconnectoT

Manual
transmission
modela

@

1

Ignition

key

2

Inhibitor
switch

N
P

positions
ON

I
2

D
R

positions
OFF

3
D
C
D
D
solenoid
valve

4

Function
test
connector

5
Inhibitor

relay

EF712

Fig
ET
31

Checking
B
C
D
D
circuit
with
function
tf
st
connf
ctor

Automatic
transmiMion
modtla

ET
17

r

ADJUSTMENT
OF
SET

PRESSURE
OF
BOOST

CONTROLLED
DECELERATION

DEVICE
B

C
D
D

Generally
it
is

unnecessary
to

ad

just
the
B
C
D

D
however
if
it

should

become

necessary
to

adjust
it

the

procedure
is

as
follows

Prepare
the

foUowlnB
tools

I

Tachometer
to
measure
the
en

gine

speed
while

idling
and
a
screw

driver

2
A

vacuum

gauge
connecting
pipe

Note
A

qui
k

response
type
boost

gauge
such
as
Bourdon
s

type
is

recommended
a

mercury

type

manometer
should
not
be
used

To

properly
set
the

B

C
D
D

set

pressure

proceed
as

follows

I

Remove
the

harness

of
solenoid

valve

TO
D
D

solenrod

VT

FJ

1
B
C
D
D

solenni

valve
harness

J

ri

y

EF262

F
g
ET

32
Removing
harneS5

of

solenoid

valve

2
Connect
rubber
hose
between

vacuum

gauge
and
intake
manifold
as

shown

Fig
ET

33

Connecting
vacuum

gauge

3

Warm

up
the

engine
until
it
is

heated
to

operating

temperature

Then

adjust
the

engine
at
normal
Engine
Tune

up

idling
setting
Refer
to
the

item

Idling
Adjustment
in

page
ET
II

Idling

engine
speed

Manual
transmission

750

rpm

Automatic
transmission

in

D

position

650

rpm

4

Run
the

engine
under
no

load

Increase

engine
speed
to
3
000
to

3
500

rpm
then

quickly
close
throttle

valve

5
At

the
time
the

manifold
vacuum

pressure
increases

abruptly
to
600

mmHg
23
62

inHg
or
above

and

then

gradually
decreases
to
the
level

set
at

idling

6
Check
that
the

B
C
D
D
set

pres

sure
is
within
the

specified
pressure

Specified

pressure
0
m
sea
level

and

760

mmHg
30

inHg
atmos

pheric
pressure

Manual
transmission

510
to

550

mmHg

20
1
to
21
7

inHg

Automatic
transmission

490
to
530

mmHg

19
3
to
20

9

inHg

Note

When

checking
the
set

pressure

of
B
C
D
D

find
the

specified
set

pressure
in

Figure
IT

36
from
the

atmospheric
pressure
and
altitutde

of
the

given
location

For

example
if
a

manual
transmis

sion

model
vehicle
is

located
at

an

altitude

of
1
000
m

3
280
ft
the

specified
set

preSsure
for
B

C
D
D

445

mmHg
17
5

inHg

7

If
it
is

higher
than
the
set

level

turn
the

adjusting
screw

counter

clockwise

or
nut

clockwise
until

correct

adjustment
is

made

Non
California

models

Adjusting
screw

type

California

models

Adjusting
nut

type

Note
When

adjusting
B
C
D
D

for

California

models
turn

adjusting

nut
in

or
out

with
lock

spring
in

place

Always
set

lock

spring

prop

erly
to

prevent

changes
in
set

pres

sure

ET

18
Non
california

models

1

Adjusting
screw

2

Cover
e

ET037

California
models

r

1

Adjusting
nut

2

Lock

spring

EC692

Fig
ET
34

Adjusting
Bet

pressure

8

Race
the

engine
and
check
for

adjustment

9
If
it
is

lower
than
the
set
level

turn
the

adjusting
screw
or

nut
until

correct

adjustment
is
made

10
Race
the

engine
and
check
for

adjustment

If

engine
speed
cannot

be
decreased

to

idling
when

checking
B
C
D
D
set

pressure
proceed
as
follows

When
the

engine
speed
does

not
fall

to

idling
speed
it

is

necessary
to

reduce
the

negative
idling

pressure
of

the
manifold
to
lower

than
the
set

pressure
of
the
B

C
D

D
The

engine

speed
will
not

drop
to

idling
speed

when
the

negative
idling
pressure
is

higher
than
the

set

pressure
of

the

B

C
D
D

In

this
case
the

engine
must
be

labored

by
I
road
test
or
2
chassis

dynamometer
or
3

by
raising
up
rear

suspension
member
on
a

stand
accel

erating
the
vehicle
to
64
to
80

krn
h

40

to
50
MPH
in

top
gear
manual

transmission
or
in
D

position
auto

matic
transmission

and
then

releasing

the
accelerator

pedal
and

letting
the

vehicle

decelerate
After

doing
this

check

whether
the
B

C
D
D
set

pres

sure
is
at
the

predetermined
value

or

not

3
If
there

is
a
leak

remove

top

cover
from

purge
contiol
valve
and

check

for
dislocated
or

cmcked
dia

phragm
If

necessary
replace
dia

phmgm
kit

which
is
made

up
of
a

retainer

diaphragm
and

spring

I
@

1
Cover

2

Diaphragm

3
Retainer

4

Diaphragm
spring

Fig
ET
47
ET350

Carbon
caniater

purge

control
valve

Carbon
unlster

filter

Check
for
a
contaminated

element

Element
can
be
removed
at

the

bottom
of
canister

installed
on
vehicle

body

Fig
ET
48

Replacing
carbon

canister

filter

Fuel
tank

vacuum
relief

valve

operation

Remove
fuel
filler

cap
and
see
it

functions

properly

I

Wipe
clean
valve

housing
and
have

it
in

your
mouth

2

Inhale
air
A

slight
resistance

ac

companied
by
valve
indicates
that

valve
is
in

good
mechanical
condition

Note
also
that

by
further

inhaling
air

the
resistance
should
be

disappeared

with
valve
clicks
Engine
Tune

up

3
If
valve

is

clogged
or
if
no
resist

ance
is

felt

replace
cap
as
an
assem

bled
unit

r

u

ET369

Fig
ET
49
Fuel

filler
cap

CHECKING

CATALYTIC

CONVERTER

INSPECTION

Preliminary
inspection

Visually
check
condition
of
all

component
parts
including
hoses

tubes
and
wires

replace
if

necessary

Refer
to

Inspection
of
A
I

S
on

page
EC
17

Catalytic
converter

Whether

catalytic
converter
is
nOf

mal
or
not
can
be
checked

by
ob

serving
variation
in
CO

percentage

The

checking
procedure
is

as
follows

Apply
parking
brake
Shift

gears

into

Neutral
for
manual
transmission

and
Neutral
or
Park
for
automatic

transmission

1

Visually
check

catalytic
converter

for

damage
or
cracks

2
Remove
air

hose
between
5

way

connector
and
air

check
valve

Plug
the

disconnected
hose
to

prevent
dust

from

entering
Refer
to

page
ET
12

3
Check
carburetor

pipes
for

proper

connection

4

Warm

up
engine
sufficiently

5
Race

engine
1
500
to
2
000

rpm

two

or
three
times
under
no
load
then

run

engine
for

one
minute
at

idling

speed

6

Adjust
throttle

adjusting
screw

until

engine
attains
to

specified
speed

Refer
to

page
ET
12

7

Check

ignition
timing
If

neces

sary

adjust
it
to

specifications
Refer

to

page
ET
10

ET
23
8

Adjust
idle

adjusting
screw
until

specified
CO

percentage
is

obtained

Refer
to

page
ET
12

9

Repeat
the

adjustment
process
as

described
in

steps
5
to

8
above
until

specified
CO

percentage
is

obtained

Note

Adjustment
in

step
9
should
be

made
ten
minutes
after

engine
has

warmed

up

10
Race

engine
1
500
to
2
000

rpm
two
or
three
times
under

no
load

and
make

sure
that

specified
CO

per

centage
is
obtained

I
1
Remove

cap
and
connect
air

hose
to
air
check
valve

If

idling

speed
increases

readjust
it

to

specified
speed
with
throttle
ad

justing
screw

12
Warm

up
engine
for
about
four

minutes
at
2
000

rpm
under
n
load

13
Measure

CO

percentage
at

idling

speed
After

step
12
has
been
com

pleted
wait

for
one
minute
before

making
CO

percentage
measurement

14

If
CO

percentage
measured
in

step
13
is
less
than
0
3
the

catalylic

converter
is

normal

15
If
CO

percentage
measured
in

step
13
is

over
0
3
recheck
A
I
S

and

replace
air

check
valve
Then

perform
inspection
steps
12

and
13

16
If
CO

percentage
is
still

over

0
3
in

step
15

catalytic
converter
is

malfunctioning
Replace
catalytic
con

verter

CHECKING
FLOOR

TEMPERATURE

WARNING
SYSTEM

INSPECTION

Floor

warning
temperature

system

Apply
parldng
brake
Shift

gears

into
Neutral
for

manual
transmission

and
Neutral
or
Park
for
automatic

transmission

1

Ensure
that
floor
tern

perature

warning

lamp
lights
when

ignition

switch
is

turned
to
the
S

position

If
not
check

lamp
for
burned

bul
bs

Engine
Tune

up

SERVICE
DATA
AND

SPECIFICATIONS

Ignition
timing
and

idling

Manual
transmission

Automatic
transmission

in
D

position

Valve

clearance

Cold
Intake

Exhaust

Intake

Exhaust
Hot

Belt
tension

Fan

Air

pump

Air

coo

compressor

Pressure

Compression
pressure
at
350

rpm

Standard

Minimum

Radiator

cap
relief

pressure

Cooling
system

Leakage
testing
pressure

Battery
specific

gravity
at
200C
680F

Distribu
tor

Point

gap

Air

gap

Dwell

angle

Condenser

capacity

Condenser
insulation

resistance

Spark
plug

Gap
degree
rpm
120
B
T
D

C
j750
Non
Calif

models

100

B
T
D

C
j750
California
models

degree
rpm
l20B

T
D

C
j650

mm
in

mm
in

mm
in

mm
in
0
20
0
008

0
25

0
010

0
25
0
010

0
30
0
012

mm
in

mm
in

mm
in

kg

lb
8
to
12
0
315
to
0
472

8to
12
0
315

to
0
472

8

to
12
0
315
to

0
472

10
22
is

applied

kg
cm2

psi

kg
em2

psi

kg
em
2

psi
12
0

171

9
0
128

0
9

13

kg
cm2

Psi
1
6
23

1

26

mm
in

mm
in

degree

IF

Mil
0
45
to
0
55
0

018
to
0
022

0
2
to
0
4
0

008
to
0
016

490
to
550

0
20
to
0
24

5

mm

in
0
8
to
0
9
0
031
to
0
035

Breaker

points
type

1

0
to
1
1
0
039

to
0
043

Transistor
ignition
type

Checking
CO

percent
at

idling
speed
No
air

Manual
transmission
model

rpm

Automatic
transmission
model

rpm

Adjustment
of

operating
pressure
of
B

C
D
D

B
C
D
D

set

pressure

Manual
transmission

Automatic

transmission
2
1

1
750

2
1
1
650

mmHg
in

Hg

mmHg
in
Hg
510
to
550
20
1

to
21
7

490
to
530
19
3
to
20
9

ET
25

Engine
Mechanical

GENERAL
DESCRIPTION

MODEL

L20B
ENGINE

CYLINDER
BLOCK

CRANKSHAFT

PISTON
AND
CONNECTING
ROD

CYLINDER
HEAD
CONTENTS

EM
2

EM
3

EM
3

EM
3

EM
3
CAMSHAFT

VALVE
MECHANISM

CAMSHAFT
DRIVE

MANIFOLDS

out
smooth

dependable

power

The

cylinder
block
is
cast
as
a

single

unit

and

featllres
deep
skirting
This

engine
is

equipped
with
a

single
2

barrel
downdraft
carburetor
that
in

corporates
a

special
device
to
control

emissions
MODEL
L20B

ENGINE

The
L20B

engine
features
O
H
C

valves

wedge
shaped
combustion

chamber
aluminum
head
and
a

fully

balanced
5

bearing
crankshaft
to
turn

Main

specifications

Oisplacemen
t
cc

cu
in

Bore
x
stroke

mm
in

Compression
ratio

Ignition

timing

Degree
B

T
O
C

rpm
MIT

AlT

MIT
Manual
Transmission
EM535

Fig
EM
Cross
sectional
view

L20B

1

952
1191

85

X
86

3
35
x
3
39

8
5

12
750

Non
California

model

10
750

California

model

12
650
in
0
position

AIT
Automatic
Transmission

EM

2
EM
3

EM
3

EM
3

EM
3

CYLINDER
BLOCK

The

cylinder
block
a
mono
block

special

casting
structure

employs
a

five
bearing

support

system
for

quiet

ness

and

higher
durability

The

cylinder
bores
are
surrounded

by
cooling

jackets
and
machined
di

rectly
in
the
block
The
oil

ways
in
the

block

are
arranged
so
that
the

full
flow

oil
filter
is

directly
attached
to
the

right
hand
side
of
the
block

EM536

Fig
EM

2
Cylinder
block

CRANKSHAFT

The
crankshaft
is

a

special
steel

forging
Fully
balanced
it
turns
out

smooth

dependable
power
at

high

speed

The
L20B

engine
uses

eight
balance

weights

Main

bearings
are
lubricated

by
oil

pumped
through
the
main
oil

gallery

and
the
oil
holes
which
run
in

parallel

with

cylinder
bores
There

are

oilways

drilled
in

the
crankshaft
for
the
lubri

cating
oil
The
center
main

bearing
is

equipped
with
thrust
washers

to
take

up
end

thrust
of
the
crankshaft

r

I

I

PRELIMINARY
CLEANING
AND

INSPECTION

DISASSEMBL
Y

PRELIMINARY

CLEANING
AND

INSt

ECTION

Before

disassembling

engine
note

the

following

I
Fuel

oil
or
water

may
leak

past

cylinder
head
and
block
Prior
to

disassembling
check

cylinder
head

1
1ltermal
vacuum
valve

2
Check

valve

3
Altitude

compensator

in

air
cleaner

4
Air

gallery
pipe

S

Auto
choke

6
Automatic

temperature

control
air

cleaner

7
Anti
8ackfire
valve
A
B

valve

8
Boost
Controlled

Deceleration

Device
Bee
D
D

9
P
c
v

valve

to
Air
relief
valve

11
E

G
R

control
valve

12
B
C
D
D

control
valve
and

solenoid
valve

13

Emergency
air

relief
valve

14
Air

pump
air
cleaner

IS
Carbon
canister

16
Air
control

valve

11
Air

pump
Engine
Mechanical

ENGINE

DISASSEMBLY

CONTENTS

EM
4

EM
4
PISTONS
AND
CONNECTING
RODS

CYLINDER

HE
AD
EM
7

EM
7

front
chain

cover
oil

pan
and
oil

filter

gaskets
lInd
crankshaft
and
water

pump
seals
for

signs
of

leakage
past

their

gasketed
surfaces

2
Check
carburetor
and

fuel

pump

for
condition
fuel
hoses
for

deteriora

tion
cracks

or

leakage
of
fuel

past

their

jointed
or
connected

surfaces

Fig
EM

0
Emiuion
control
devic
s

California
mod
18
E
T366

3
Remove

carburetor
air

cleaner

Remove
fresh

air
duct

Disconnect
hot
air
duct
from

air

cleaner

Disconnect
air

cleaner
to
air

pump

hose
at
air

cleaner

Disconnect
air

cleanef
to
rocker

cover

hose
at
rocker
cover

Disconnect

air
cIeaner

to
air

con

trol

valve
hose
at
air

cleaner
Cali

fornia

models

only
Disconnect
air

cleaner
to
A

B
valve

hose
at
air

cleaner

Disconnect
air

cleaner
to

related

part
vacuum
hoses
at
air

cleaner

Loosen
air

cleaner
band
bolt
and

remove
carburetor
air

cleaner
as

sembly
from

carburetor

4

Plug
up
carburetor
air

horn

to

prevent
entry
of

foreign
matter

5

Remove

alternator
drive

belt

alternator
and

alternator
bracket

EM
4
6

Remove
air

pump
drive

belt
cool

er

compressor
and
idler

pulley
if

so

equipped

7
Remove
starter
motor
from
trans

mission

8

Visually

inspect
cylinder
head

cylinder
block
rocker
C
Ner

front

chain
cover
oil

pan
and
all
other
outer

parts
for
oil
water
and
fuel
leaks

breakage
or

missing
parts
such

as
bolts

and
nuts

9

Check

piping
and
electrical
cir

cuits
for
deterioration

breakage
fit

tings
discontinuity
or
insulation

DISASSEMBLY

To

remove

engine
from
vehicle

refer
to

the
instructions
under
the

Engine
Removal

and
Installation

ER
section

I

Remove
transmission
from

en

gine

2
Remove

clutch

assembly
from

flywheeL

3

Thoroughly
drain

engine
oil
and

coolan
t

by

removing
drain

plugs

Store

engine
oil
and

coolant
if

they

are

to
be

used

again

4
Place

engine
assembly
on

engine

stand

I

Remove

cooling
fan

2

Remove

right
engine

mounting

bracket

3

Remove
oil
filter
with
Oil

Filter

Wrench
STI9320000

4

Remove
oil

pressure
swi

tch

5

Install

engine
attachment
to

cylinder
block

utilizing
bolt

holes
in

alternator

bracket
and

water
drain

hole

6
Set

engine
on
stand

Engine
Attachment

ST05260001

Engine
Stand

ST050I

SOOO

Engine
Mechanical

SERVICE
DATA
AND
SPECIFICATIONS

GENERAL
SPECIFICATIONS

Engine
model
L20B

Cylinder
arrangement

Displacemen
t

Bore
and
stroke
4
in

line

cc
co
in

mm
in
1

952

J
19
1

85
x

86
3

35
x
3
39

O
H

C

I

3
4
2
Valve

arrangement

Firing
order

Engine
idle
rpm

Manual
transmission

Automatic
transmission
in
D

range
750

650

8
5

Compression
ratio

Oil

pressure
Warm
at
2

000

rpm

kg
cm2

psi
3
5
to
4
0
50

to
57

SPECIFICATIONS

a
Valve
mechanism

Valve

clearance
Warm

Intake

Exhaust

Valve
clearance
Cold

Intake

Exhaust

Valve
head
diameter

Intake

Exhaust

Valve
stem
diameter

Intake

Exhaust

Valve
length

Intake

Exhaust

Valve
lift

Intake
and
exhaust
mm
in

0
25
0
010

0
30
0
012

mmOn

0
20
0
008

0
25
0
010

mm
in

42
0
to
42
2
1
654

to
1

661

35

0
to
35
2
1

378
to
1
386

mm
in

7

965
to
7
980
0
3136
to

0
3142

7
945
to
7
960
0
3128
to

0
3134

mmOn

114
9
to
115
2
4
524
to
4
535

115
7
to
116
0
4
555
to
4

567

mmOn

Valve

spring
out

of

square
mm
in
10
5
0
413

less
than
1

6
0
063

Valve

spring
free

length
mm
in

Intake
and
exhaust
Outer

Inner
49
98
1
968

44

85
J
766

EM
27

r

direction
when
hoses
are

assembled

3
Ensure

that
clearance
between

radiator

hose
and

any
adjacent
parts
is

30
mm
I
181
in
minimum

On
mod

els

equipped
with
air

conditions
a

minimum
clearance
of
18

mm
0
709

in
should

exist
between

compressor

and
hose

4
Ensure

that
clearance
between

shroud
and
fan
is

even
at

any
place

Note
Be

careful
not
to

damage
radia

tor
fins
and

core
tube
when
in

stalling

INSPECTION

Radiator

cap
should
be

checked
for

working
pressure
at

regular
tune

up

intervals
First

check
rubber
seal
on

cap
for

tears
cracks
or
deterioration
Cooling
System

after

cleaning
it
Then

install
radiator

cap
on
a

tester
If

cap
does
not

hold
or

will

not
release
at
the

specified
pres

sure

replace
cap

Fig
CO
9

Telting
radiator

cap

Also

inspect
radiator
for

leakage

using
cap
tester

and

applying
a

pres

sure

of
1

6

kg
cm
22
8

psi
If
a

leakage
is

detected

repair
or

replace
radiator

Fig
CO

IO

Testing
cooling
6ystem

pUS
ure

SERVICE

DATA
AND
SPECIFICATIONS

Thermostat

Valve

opening
temperature
oC
F

Maximum
valve

lift
mm
oC

inj
F

Radia
tor

Type

Manual
transmission

Automatic

transmission

Cap
relief

pressure

Cooling
system

Leakage
testing
pressure

Capacity

Manual
transmission

Automatic
transmission

Fan

Number
of
blades
x
outer
diameter

Without
air

conditioner
mm

in

With
air

conditioner
mm
in
kg
em

psi

kg
em

psi

liters
US

qt
Imp

qt

liters
US

qt
Imp
qt

CO
6
Temperate

Frigid
type
Tropical
type

type

80
5

to
83
5
86
5
to
89
5
75
to

78

177
to
183

187
to
193

167
to
172

8
95

8
100
8
90

0
31
203
0
31
212
0
31

194

Corrugated
fin

type

Corrugated
fin

type
equipped
with

oil
cooler

0
9

1
3

1
6
22
8

with

heater

8

0
8
Ii
7

7
8
8
Y

6
J
i
without
heater

74
7J
i6

1i

7
2

7
X
6

X

7
x

380

15

8
x

380

15

FLOAT
SYSTEM

There
IS

only
one

float
chamber

while
two
l

arburetor

systems
primary

Jnd

st
l

ondary
are

provided

Fuel
fed
from
the
fuel

pump
flows

through
the
filler
and
needle

valve
into

the
flo
t
chamber
A

constant
fuel

level

is
maintained

by
the
float
and

needle
valve

Because
of

the
inner
air

vent

type

of

the
float
chamber
ventilation
the

fuel

consumption
will
not

be
in

fluenced

by
some
dirt
accumulated
in

the
air

deaner

The
needle
valve

includes

special

hard
steel
ball

and
will
not

wear
for
all

its

considerably

long
use
Besides
the

inserrion

of
a

spring
wiU

prevent
the

flooding
at

rough
road

running

BOOST

CONTROLLED

DECELERATION
DEVICE

B
C
D
D

A

Boost
Controlled
Deceleration

Device
B

C
D

D
serves
to

reduce
the

hydrocarbons

He
emitted
from
en

gine
during
coasting

The

high
manifold
vacuum

during

coasting

prevents
the
mixture

from

complete
combustion

because
of
the

reduced
amount
of
mixture

per
cyl

inder

per
rotation

of

engine
with
the

result
that

a

large
amount
of

hydrocar

bons
is

emitted
into
tile

atmosphere

The
B

C
D
D
has
been

designed
to

correct

this

problem

It

opern
tes

as
follows

when
the

manifold

vacuum
exceeds
a

pre
Engine
Fuel

determined

value
the

B
C
D
D
intro

duces

an
additional
mixture

of

opti

mum
mixture
ratio
and

quantity
into

the

manifold

by

opening
a

separate

mixture

passage
in
the

carburetor

Complete
combustion

of
fuel
is
assist

ed

by
this
additional
mixture

and
the

amount

of
H
C

contained
in

exhaust

gases
is

dramatically
reduced

During
the

transition

period
from

coasting
to

idling
the
transmission

produces
a

signal
which
turns
on
the

vacuum
control

solenoid
valve
As
this

takes

place
the
valve
is

lifted
off
its

seat

opening
the

vacuum
chamber
to

the

atmosphere
The
mixture

control

valve
is
then

closed

returning
the

engine
to
the

predetermined
idling

speed

On
manual

transmission
models

this

system
consists

of
B
C
D
D

vacuo

urn
control

solenoid
valve

speed
de

tecting
switch
and

amplifier

On
automatic

transmission

models

it
consists

of
B
C
D
D

vacuum
con

trol

solenoid
valve

and

inhibitor

switch

B
C
D
D

operation

Diaphragm
I

Qj
monitors
the

mani

fold

vacuum
and

when
the

vacuum

exceeds
a

pre
fetermined
value
acts
so

as

to

open
the

vacuum
control
valve

@
This
causes

the
manifold

vacu
urn

to
be

introduced
into
the

second

vacuum
chamber
and

actuates
dia

phragm
ll@

When

diaphrngm
II

operates
the

mixture

control
valve

@
opens
the

passage
and
introduces
the
additional

mixture
into

the
manifold

EF

18
The
amount
of

the
mixture

is
con

trolled

by
the

servo
action

of
the

mixture
control

valve

CID
and

vacuum

control

valve

@
so

that

the
manifold

vacuum

may
be

kept
at
the

pre

determined

value

The
amount

of
mixture

depends

mainly

upon
the

coasting
air
bleed

II@
while
the
mixture
ratio

is
deter

mined

by
the

coasting
jet

@
and

coasting
air
bleed

@
See

Figure

EF
31

Vacuum

control
solenoid

valve

operation

Manual

transmission
models

The

vacuum
control

solenoid
valve

is

con
troDed

by
a

speed

detecting

switch
that
is

actuated

by
the

speed

ometer
needle

As
the
vehicle

speed
falls

below
10

MPH
this
switch
is
activated

pro

ducing
a

signal
This

signal
actuates
the

amplifier
to

open
the
vacuum
control

solenoid
valve

Automatic

transmission
models

When
the

shift
lever
is
in
N

or

P

position
the
inhibitor
switch

mounted
on
the
transmission

turns
on

to

open
the
vacuum

control
solenoid

valve

I
Air

jet

2

Diaphragm
II

3
Mixture
control
valve

4

Coasting
air

bleed
II

5
Mixture
air

passage

6

Secondary
baHel

7
Intake
manifold

8
Boost

passage

9
Vacuum
control
solenoid

valve

10
Vacuum
control
valve

II

Diaphragm
I
Engine
Fuel

12

Secondary
main

jet

13

Coasting
jet

14

Coasting
air
bleed
I

15
Inhibitor
switch
N

P

ON
for
automatic

transmission

16

Amplifier

1
7

Speed
de

tecting
swi
tch
below

10
M
P
H
ON

for
manual

transmission

1

W
j

I

t

i
J

l

J
18

Ignition
switch
CID

1
1

fI3
6

@
I

r
101

@
i

r

@

JJ

Note
Broken
line

applies
only
to
Automatic
Transmission

I

Ignition
switch

2

Amplifier

3

Speed
detecting
switch
below

10
M
P

H
ON
for
manual

transmission

4
Inhibitor
switch
N
p

ON
for
automatic

transmission

5
Solenoid
valve

6
Vacuum
control
valve

7
Altitude

corrector

LlJ

I

I

l

f

L8
J

l
EF231

Fig
EF
31
Schematic

drawing
of
B
C
D
D
Non

California
models

1

J
ru

I

r

lJ

i7

I
To
intake

manifold

To
air

cleaner

E
F235

Note
Broken
line

applies
only
to
Automatic
Transmission

Fig
EF
32
Schematic
drawing
of
RC
D
D

California
models

EF
19